Effect of the viscosity of solutions on the activation energies of reactions of the solvated electron

The effect of the viscosity of solutions on the rate constant and activation energy of reactions of the solvated electrons with nitrobenzene, C₆H₅NO₂, carbon tetrachloride, CCl₄, and acetone, CH₃COCH₃, were studied. The effect on the rate constants is inversely proportional to the 0·66 power of the viscosity, η, [k(e_solv⁻+S) ∞ η^−0·66]. The activation energies of these reactions, E(e_solv⁻+S), are linearly related to the activation energies for viscous flow of solutions E_vis, i.e. E(e_solv + S) = α. E_vis + β). It is suggested that the valueof β represents the activation energy for the accommodation of the extra electron in the substrate molecule.